Harvest sprouting broccoli, Brussels sprouts and leeks.

Stake or earth up any Brussels sprouts stalks that look leggy and vulnerable to wind rock. Pick the biggest sprouts from low down the stalks first.

Lift Jerusalem artichoke tubers for cooking.

Parsnips, swede, celeriac and turnips can still be harvested, if this has not been done already. Parsnips improve in flavour with a touch of frost, but other root vegetables are better harvested earlier in the winter, so that they are safe from frost and easily accessible from the kitchen. They can be stored in the shed, or in a shallow trench, covered to protect it from frost.

Start forcing rhubarb. Place a large bucket, dustbin or forcing jar over the crown to encourage the fresh, pink shoots to form in the darkness. A few shovels of manure, straw and poultry manure pellets thrown over the top will create extra warmth to speed up the process.

Chicory and seakale can be forced as well. Dig up selected chicory roots, pot them up, and position them in a dark warm place (10-13°C/50-55°F), with an upturned pot over them. The tasty chicons will appear in three to six weeks. Seakale is best forced outside at seasonal temperatures, with an upturned pot or cardboard box/tube over the top to exclude the light.

In mild areas, sow broad beans in pots, placing them in a cold frame or unheated greenhouse. These will be ready for planting out in spring.

Other crops can also be germinated in pots on the windowsill, and then grown on in the greenhouse for planting out in February. This should result in early crops next year. Lettuces, summer brassicas (e.g. cabbages and cauliflowers), radishes, tiny round carrots, spinach, salad onions and turnips are all suitable.

Onions from seed need a long growing season, and you could sow them now in a heated propagator, for planting out in March. This is how exhibition growers manage to get large bulbs for shows.

The mildest south-west regions of the country could get away with sowing seed directly into the ground - if the winter is mild, and the ground has been covered for the previous few weeks. Tunnel cloches or polythene sheeting are ideal covers. Lettuces, radishes, early peas, broad beans, spinach and salad onions could work from such early sowings.

Plan a rotation system for vegetable plots to ensure the same crops are not grown in the same beds year after year to help prevent disease build-up.

Clear remaining spent crops from the vegetable garden.

If you have not done so already, dig over and incorporate soil improvers into vacant areas of the vegetable plot. You can cover these areas with thick polythene to keep the soil dry and make it easier to work in the spring - particularly useful for heavy clay soils. Clear polythene will increase the soil temperature, enabling earlier sowings in spring. Black polythene and thick carpet will suppress weeds.

If the weather is reliably dry and frosty, then heavy soils can benefit from being left exposed - the frosts will kill pests and improve soil structure by the continual freezing and thawing of soil water.

Save egg boxes as they will come in handy for potato chitting next month. Source your seed potatoes if you have not already done so.

When gardening on wet soils work from a plank of wood, rather than treading on the bed, to avoid compacting the soil.

Improve the drainage of heavy soils by working in lots of organic matter. Grit will only be effective when used in conjunction with organic matter.

Pest & disease watch

Place mice controls near stored vegetables.

Regularly check stores and remove any rotting or mouldy specimens.

Ensure that crops remaining in the ground, and new sowings under cloches, are protected from mice.

Slugs can still pose a threat, and slug controls are necessary now, as always.

Pigeons are serious pests of brassicas and other vegetables. Cloches, frames of netting or fleece, and metal cages will help to keep them away from vulnerable crops.

Pick yellowing leaves off Brussels sprouts and other brassicas promptly, to prevent spread of grey mould and brassica downy mildew.

Remove all remaining plant debris from the vegetable plot. Do not compost any diseased material such as blight-infected potatoes, onions suffering from white rot and any crops with rust. Burn or bin the diseased material, or bury it more than 60cm (24in) deep in the ground.

Digging-over in winter exposes soil pests to frost and bird predators.

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